WASP-36b: A new transiting planet around a metal-poor G-dwarf, and an investigation into analyses based on a single transit light curve

TL;DR

This paper reports the discovery of a transiting exoplanet around a metal-poor G-dwarf star, WASP-36b, and examines how analyzing a single transit light curve affects the accuracy of system parameter estimates.

Contribution

It presents the discovery of WASP-36b and investigates the reliability of system parameters derived from individual versus combined transit light curves.

Findings

Consistent system parameters obtained from individual light curves.

Analysis of multiple light curves mitigates effects of correlated noise.

WASP-36b has a mass of 2.30 Jupiter masses and radius of 1.28 Jupiter radii.

Abstract

We report the discovery, from WASP and CORALIE, of a transiting exoplanet in a 1.54-d orbit. The host star, WASP-36, is a magnitude V = 12.7, metal-poor G2 dwarf (Teff = 5959 \pm 134 K), with [Fe/H] = -0.26 \pm 0.10. We determine the planet to have mass and radius respectively 2.30 \pm 0.07 and 1.28 \pm 0.03 times that of Jupiter. We have eight partial or complete transit light curves, from four different observatories, which allows us to investigate the potential effects on the fitted system parameters of using only a single light curve. We find that the solutions obtained by analysing each of these light curves independently are consistent with our global fit to all the data, despite the apparent presence of correlated noise in at least two of the light curves.